四川坪头水电站白云岩砂化特征及发育分布规律  

Characteristics and distribution of dolomite sandification at Pingtou Hydropower Station

作　　者：张良喜[1,2,3] 张海泉[1,2] 赵其华[1,2] 何文秀[1,2] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]成都理工大学环境与土木工程学院,四川成都610059 [3]四川省地质矿产勘查开发局攀西地质队,四川西昌615000

出　　处：《人民长江》2012年第19期42-44,78,共4页Yangtze River

基　　金：国家重点基础研究发展"973"计划项目(2011CB013501);长江学者和创新团队发展计划资助项目(IRT0812)

摘　　要：以四川美姑河坪头水电站坝址区深部白云岩砂化为研究对象,采用现场调查与室内化学全分析实验相结合的方法,对白云岩砂化物质结构特征及发育分布规律进行研究。研究认为:随着白云岩岩溶砂化作用的发展,白云岩砂化物质结构演化特征为白云岩砂—白云岩(粉)—粉质黏土。砂化物质主量元素的化学迁移过程具体表现为:易溶物质CaO、MgO的不断溶蚀淋失,难溶物质SiO2的明显富集,Al2O3、Fe2O3在后期形成粉质黏土过程中得到一定程度富集。白云岩砂化发育分布受地层岩性、地质构造、斜坡变形破坏影响较大,平面上表现为不均一性,而垂向上则表现为明显的分层特征。这一研究成果,对认识该地区这种特殊的岩溶现象有特殊意义。Taking the deep dolomite sandification at dam site area of Meiguhe Hydropower Station in Sichuan Province as a research object and by the methods of in-site investigation and indoor chemical analysis,we study the structural characteristics and development law of dolomite sandificated materials.The research results show that with sandification development of dolomite,the structural evolution process of sandificated dolomite materials are dolomite sand-dolomite（powder）-powdered clay;the chemical migration process of the main elements are continuous solution of soluble substance CaO,MgO and obvious enrichment of insoluble matter SiO2,some extent enrichment of Al2O3,Fe2O3 in clay formation process in later period.The sandfication and distribution of dolomite are influenced by formation characteristics,geological structure,deformation and failure of slope and characterized by inhomogeneity in plane and obvious stratification phenomenon in vertical direction.The research achievement has special significance for understanding the special karst phenomenon in this area.

关 键 词：白云岩砂化 基本特征 分布规律 岩溶 坪头水电站 四川 

分 类 号：P642[天文地球—工程地质学]